Temperature Data Processing
ODP logging contractor: LDEO-BRG
Hole: 1119C
Leg: 181
Location: New Zealand Continental
Shelf (SW Pacific Ocean)
Latitude: 44° 45.33' S
Longitude: 172° 23.61' E
Logging date: August, 1998
Bottom felt: 407.2 mbrf
Total penetration: 494.8 mbsf
Total core recovered: 442.2m (89.4
%)
Water Depth: 406 mbrf
Temperature Tool Used: LDEO-TLT
Depth versus time recording available: YES
Logging
Runs
Logging string 1: DIT/HLDS/APS/HNGS
Wireline heave compensator was used to
counter ship heave.
Tool
Information
The LDEO-TLT tool is a self-contained, high
precision, low-temperature logging tool that is attached to the bottom of the
Schlumberger tool strings. The tool provides two temperature measurements (in
degree Celsius, recorded by a fast-response and a slow-response thermistor. The
fast-response thermistor, though low in accuracy, is able to detect sudden,
small temperature excursions caused by fluid flow between the formation and the
borehole. The highly accurate, slow-response thermistor can be used to estimate
heat flow. Pressure and the two temperature measurements are recorded as a
function of time: conversion to depth can be based on the pressure reading
(Legs 123-157) or, preferably, on simultaneous recording (by Schlumberger) of
depth and time (Legs 159-181).
Data
Processing
During this leg depth versus time data was
recorded on a personal computer (part of the L-DEO digital logging data
acquisition system in the ODP Downhole Measurements Laboratory aboard the
JOIDES Resolution) with input from the Schlumberger MAXIS computer. The depths
recorded through this system are the same used by Schlumberger to measure cable
length as recorded in the logging data files. These depth data were merged with
the data recorded in memory by the Temperature Logging Tool (TLT) by matching
absolute time in the two data sets. Time versus depth data from the MAXIS was
available during logging at all holes. The depths in the processed files are
reported in meters below sea floor (mbsf). At each hole, the constant depth
shift applied to the original temperature logs was the same as that applied to
all of the other logs; it is given in meters below rig floor (mbrf) in the
header of the processed files.
Information about the temperature logging
operations can be found in the Site Chapter (Operations, Downhole Measurements,
and Heat Flow sections), ODP IR volume 181.
For further information about the processing,
please contact:
Cristina
Broglia
Phone: 845-365-8343
Fax: 845-365-3182
E-mail: Cristina Broglia